1 FIELD OF THE INVENTION
The present invention relates to a floor coating liquid applying machine having a propelling machine body, a liquid feed device mounted on the machine body for feeding floor coating liquid to a floor surface and a feed pump attached to the liquid feed device for feeding the floor coating liquid from a liquid tank.
2 DESCRIPTION OF THE RELATED ART
A floor coating liquid applying machine of the above-noted type is known from e.g. a Japanese patent application gazette No. 1-240353. In this machine, a plurality of feed nozzles, comprising liquid feed devices, are disposed side by side in the transverse direction of the machine body and a liquid feed pump of a fixed delivery type is employed for distributing floor coating liquid from a liquid tank to the feed devices, so that the coating liquid can be uniformly applied onto an entire surface of a predetermined width corresponding to a travelling passage of the machine body.
The problem with the above machine is that it takes a long time to dry the applied floor coating liquid.
That is, for preventing clogging by the liquid, each of liquid passages respectively extending to the feed nozzles has a relatively large cross section. Accordingly, it is difficult to restrict the amount of liquid discharged through the nozzle. Further, restriction of amount of discharged liquid is also difficult for the fixed delivery pump because of its structural and designing limitations. Consequently, with this conventional machine, the amount of floor coating liquid applied to the floor per unit area tends to be excessive. This means that the machine consumes a large amount of liquid to treat a floor surface of a fixed area and also that the drying operation of the liquid takes a long time.
As to the second-mentioned problem, the prior art has suggested use of a heater incorporated in an applying member for promoting drying of the liquid by heat discharged thereby (Japanese laid-open patent gazette No. 63-315169).
However, this machine still has some room for improvement also. First, the finish of the treated floor tends to be poor because contact between the heater member and the floor surface interferes with development of glossiness and water evaporation of the coating liquid. Second, the machine can not yet achieve significant speed-up of drying operation.
Taking the above state of the art into consideration, the primary object of the present invention is to provide an improved floor coating liquid applying machine which can feed a proper amount of floor coating liquid while effectively avoiding clogging of liquid passage by the liquid thereby to provide good floor finish and to significantly speed up the drying operation of the applied liquid.